On Ramadan, the lack of arctic muslims, and why autumn is ideal for the Yom Kippur

While buying diapers on the weekend from my muslim neighbors, I learned that the holy month of Ramadan has just recently started. The hot weather made me realize that the Ramadan fast cyclicly varies from an easy obligation to one which is very hard. Fasting in summer implies abstaining from drinking while it's hot, and fasting for more hours a day. In fact, a muslim living north of the arctic circle would not survive a summer Ramadan, implying that no muslim can permanently live in arctic (or antarctic) regions. It also made me think about the Yom Kippur fast which turns out to be ideally placed in the autumn.

Ramadan and the lunar calendar

Both the Jewish Calendar and the Muslim calendar are lunar based. However, there is a notable difference between the two. The muslim year is exactly 12 lunar months. Since 12 lunar months are less than 365.25 days, the muslim holidays migrate throughout the year. This posed no real problem given that the original Arab muslims were nomads, and the time of year meant relatively little, at least with respect to their holidays. Jews were an agrarian society for centuries. It is thus no surprise that their calendar had to adjust itself to keep it from migrating, keeping the holidays in sync with the solar year. Thus, the Jewish calendar has leap years keeping the cycle intact (well, almost! see box below). Incidentally, this calendar is originally Babylonian who were agrarians too (with some of the Mesopotamian gods still surviving in current hebrew month names, such as Tammuz).

A lunar synodic month (i.e., new moon to new moon) is 29.53 days. This implies that each year, the month of Ramadan occurs earlier by 365.25 days - (29.53 days)*12 = 10.89 days. Namely, over 365.25 / 10.89 = 33.5 years, the Ramadan (and other muslim holidays) migrates through the seasons.

When the Ramadan fast occurs in winter, the days are short. Since the fast is only during the day, the fast is shorter as well. Moreover, the lower temperatures imply that it is easier not to drink. In summer, it is the opposite. A devout muslim needs to restrain from eating for more hours a day and keeping himself from drinking when the temperatures are higher (and in the Arabian desserts they can be pretty high!).

Currently, Ramadan starts late September. In about 9 years, Ramadan will coincide with July.

If a muslim will decide to migrate north of the Arctic circle, he will find himself in a strange situation, we will have to fast continuously for 30 days. Since a human typically dies in 3-4 days without food and water (with the maximum record being 18 days), these arctic muslims will die in the name of religion (something which is actually is not new). Thus, there could be no permanent muslim colony in arctic regions.

What about Yom Kippur?

Unlike Ramadan, Yom Kippur lasts one whole day (day and night), so even if the Jewish calendar would have wondered around, it would have made no difference. Interestingly, however, it is stuck in the ideal season for it it be the shortest possible. How is that you ask? Well, Jewish days are from sunset to sunset. Since Yom Kippur always falls in autumn (in the whereabouts of the end of Sept.), it falls over a period when the days get shorter, so sunset to sunset is less than 24 hrs! We can also easily estimate by how much.

Lets suppose for simplicity that we can approximate the length of day as a sinusoidal function (there are various reasons why this is not accurate, but for our estimate, it is certainly good enough). Thus:
$$ LOD \approx 24 hr + \Delta L\sin \left( 2 \pi (t-t_0) \over 1 yr\right) $$
where ΔL is the difference between the longest and shortest day. t0 is the phase of equal day and night (i.e., spring solstice). Since Yom Kippur falls over the autumn solstice, we have $ 2 \pi (t-t_0) / 1 yr \approx \pi$. Hence, the length of Yom kippur is roughly:
$$ \Delta(LOD) \approx (1 day)\times {d(LOD) \over dt} = {(2 \pi day) \over 1 year} \Delta L \cos \left( 2 \pi (t-t_0) \over 1 yr\right) \approx -(1 min) {\Delta L \over 1 hr}$$
Namely, given ΔL in hours, Yom Kippur is shorter by the same numeric value in minutes. In Israel, summer days are typically 14 hrs long while winter days are about 10 hrs, so Yom kippur is not 24 hrs long, but roughly 4 minutes shorter. If you live near the arctic circle, you can cheat and have a Yom Kippur which is shorter than a full day by more than 20 mins. That's Kosher cheating. But you don't really get to gain a lot. The best way to really cheat big time is to cross the dateline during Yom Kippur. The catch: If you observe Yom Kippur, you wont be in any motorized vehicle. This implies that you have to walk across the dateline, and since the only place it is possible is in Antarctica, this is the place to be if you wish to cheat yourself out of Yom Kippur fast.

Hebrew holidays wonder too. A Hebrew calendar leap cycle includes 7 leap years in a 19 year cycle. Since 12 normal years + 7 leap years are on average 365.2424 days, while the average tropical solar year is about 365.2422 days, the Hebrew holidays wonder forward at a rate of 7 mins a year on average, this adds up to 1 day every 213 Gregorian years. Since the time of King David, the holidays thus shifted by about 14 days relative to their biblical time (they now occur later in the solar year). In a few centuries, the hebrew Calendar would have to have one 6 leap years cycle to correct this offset.

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Comments (20)

Leviel (not verified)

If you're a Jew living in the southern hemisphere, you'd experience Yom Kippur during the opposite season as that of the northern hemisphere, so you'd have spring. Back in the day, you'd also have celebrated the wrong harvest at Sukkot a few days later...

Oct 25, 2006

shaviv

In the southern hemisphere, Yom kippur will be slightly longer than 24 hrs, and it will slowly be moving towards summer (at a rate of 7 mins a year...). As for the wrong harvest, Sukkoth is not a harvest holiday, but the seeding/planting one! The reason is that in Israel (where the holiday came about...) it rains in winter, while is summer it is bone dry. So the harvest holiday (i.e., the Jewish thanksgiving) is in Spring (Shavuot). That is, agricultural Jews living in a wet-summer southern location, will actually be celebrating Sukkoth in the (sort of) right season... it is the North American and European agricultural Jews (are there?) which are celebrating Sukkoth in the wrong season.

Oct 25, 2006

Matt (not verified)

Actually, to quote Wikipedia, "According to the Qur'an, if fasting would be dangerous to someone's health ... that person is excused. ...but they are encouraged to feed a needy person instead." So I guess they'd be okay. This is a very funny conundrum I thought of today while leaving a local Middle Eastern restaurant, I'm glad I'm not the only one to realize it.

Oct 25, 2006

shaviv

Ah... so it would actually be an incentive for a muslim to travel to the arctic, as it would save him from fasting. As for thinking on these issues... I am sure that in a few years, when Ramadan would actually fall on the heat of summer, there will be more than two people thinking about it ;-)

Oct 25, 2006

Anonymous (not verified)

Shalom.

You are missing the point of fasting for muslims. Without getting into much detail, God knows what is in a man's heart. Having said that, if a muslim moved to the Arctic only to avoid fasting (as per your suggestion), clearly he's only deceiving himself.
As Matt pointed out that it is not obligatory on Muslims to fast under certain conditions, the one he mentioned is clearly one of them.

Regards.

Feb 11, 2007

shaviv

I hope you realize that I am mostly trying to bring some humor here without really intending to offend anyone, sort of trying to mix science with religion with humor. Clearly, I doubt that when a muslim migrates somewhere he or she really thinks about these religious "loopholes".
cheers,
-- Nir

Jun 19, 2007

Anonymous (not verified)

Dear friend, these are not loop holes in the religion. We believe that this religion is the code of life and guides the best way to lead it. There are strict orders where it is within human power to do something and there are options provided that fit in with the requirements of the whole world as there is no one algorithm to go about everything.
If you look in detail you would appreciate the point you just raised about fasting, that how the religion has dealt with it.

Another thing is that It is not good to bring humour to discussion which includes religion as these are sensitive issues. Also everyones religion should be respected so one needs to be extra careful.
Bless You

i personally think youre going about combining the 2 in the correct sort of doses.

dont let the hecklers get you down ;)

Apr 17, 2008

Anonymous (not verified)

Actually it would be a disadvantage to the Muslim to move to the Arctic, since as the article states, the devout Muslim fasts during daylight hours. To avoid fasting, the devout Muslim would have to spend Ramadan on the continent of Antarctica.

Aug 16, 2009

Anonymous (not verified)

If the duration between dawn till dusk is big enough to cause physical damage to the person, he can choose the duration in Mecca or Medina and do his fasting. This is not stated in Koran, but I think some learned islamic scholars have put their opinion on this.
Similarly if he is in a arctic winter or near arctic where the daytime can be as short a 2-4 hours, he should follow the duration in Mecca or Medina otherwise he will be decieving the very purpose of fasting.

since the jewish community leaders in past times as well as current,
took precautions ("hegdilu asot") and declared yom-kipur to last 25(damn them!!! it's hard enough as it is!!! :) )
hours instead of the traditional 24+-several minutes... one has to wonder whether
they knew of this little adjusment.
of course they would also have to know the human (jewish??) cunning and
therefor devise this to countermand it :)

Mar 21, 2008

shaviv

I also noticed that the Shabath stays longer than 24 hrs... It appears that Earth relaxes and rotates slower on the weekends ;-)
-- Nir

Ramadan is the month during which the Quran was revealed, providing guidance for the people, clear teachings, and the statute book. Those of you who witness this month shall fast therein. Those who are ill or traveling may substitute the same number of other days. Allah wishes for you convenience, not hardship, that you may fulfill your obligations, and to glorify Allah for guiding you, and to express your appreciation.”[2:185] This is a muslims favorite holiday.

I have no doubt that Ramadan is a time of both great solemnity and great joy for practising Muslims, and I have every respect for those who can observe such stringent restrictions (personally, I find Yom Kippur a great challenge, let alone a whole month of fasts).

However, my appreciation of Ramadan is dampened slightly by the call to prayer that is broadcast very loudly over speakers from nearby mosques here in Israel. Last year we were woken at around 4:00 am every day for a month, which does become a bit wearing.

Not that the call to prayer should be stopped, G-d forbid ... I just wonder whether it has to be done over a powerful sound system? Surely in earlier times it was done without technology, so it can't be a religious requirement?

Jul 20, 2008

Anonymous (not verified)

You all seem to also forget that some countries get absolutely no sunlight in winter. Does that mean a muslim is excused from fasting?? I doubt that. Same question about the very long days in the summer. In a case like that a muslim can follow Mekka's fasting times, since it is not possible to fast 24/7.
Islam is an uncomplicated religion, contrary to how many people (including muslims) conceive it. It is not there to torture or to complicate.

If a muslim moved to the Arctic only to avoid fasting (as per your suggestion), clearly he's only deceiving himself.

Apr 10, 2009

Anonymous (not verified)

Please can someone tell me whether one can fast from 6.00 am to 6.00 pm, during the Summer Months. How can one survive without water for 16 hours. Surely this cannot be good for your health.
A concerned Muslim brother.